I'm carbonating my cider in 1 gallon glass carboys and my solid rubber bungs popped off a few times so I tied them down with cable ties. Can anyone tell me if this is ok and the carboy can take the pressure. I used 4 teaspoons of sugar per 1 gallon carboy, and keep at room temperature. Thanks

2 Answers
2

Unlike glass bottles, glass carboys are not designed to hold pressure.

4 tsp in 1 gallon will produce about about 2.4 volumes of CO2. The pressure created will be significant - at a minimum 22 PSI, but likely more than that, since fermentation proceeds quicker than the CO2 will dissolve, into the beer. Assuming you have little headspace, the pressure could be easily many times that.